Transmission Speed Sensor Location: How To Replace A Bad Transmission Speed Sensor

Your transmission speed sensor is a crucial compartment of your car; once it breaks, drivers won’t be able to realize the velocities of their vehicle, leading to fatal crashes. Yet, many people neglect this part. Today, Driverevolve will discuss basic transmission speed sensor knowledge, including transmission speed sensor location, its uses, signs of a bad sensor, and so on.   

What Does A Transmission Speed Sensor Do?

The speed sensor picks up on the rotational velocity of gear or targeted cogs in the gearbox and processes that information into a computerized electric output. This data is analyzed by the transmission controllers and used to adjust shift positions and run diagnostic checks.

You might ask, what sets a vehicle speed sensor apart from a speedometer?

A car’s speedometer usually consists of a hidden motor cable inside the casing with its wire connected to a cog at the gearbox’s rear end. And as its name implies, it only governs your car’s speed.

 A transmission speed sensor is more multifunctional; thus, it replaces the old speedometer in modern cars. As it spins, it sends a message to the processor through an electrical outlet. 

This way, the controller may use the device’s readings to determine your vehicle’s velocity. It also shows whether the transmission rate or shift settings need to be changed.

Another practical use of a speed sensor is its ability to measure the actual distance you’ve traveled. It can transmit this information to the car’s odometer for other applications.

In some cars, a speed sensor may also transmit data to trigger automatic door locking at a predetermined time. Speed sensors in modern automobiles often include stabilization and steering features that improve the effectiveness of the anti-lock braking mechanism.

Transmission Speed Sensor Location 

Typically, you may find the transmission speed sensor next to the output shaft. Its placement enables it to monitor shaft rotations and velocity and then report that information through wires to the vehicle controller.

4 Bad Speed Sensor Symptoms That You Should Look Out For

Difficulties Changing The Gears 

When your automobile’s speed sensor fails, the most classic indication is increased gearbox revs, preventing the gearbox from shifting gears smoothly. So, the motor is going faster than the automobile is going.

You may also experience significant vibrations while changing gear settings, which will become more difficult as the condition progresses. This indicates that the gearbox will shift into overdrive relatively late in the driving state.

The reason is that a properly functioning speed sensor is essential for the gearbox to change in your car. This sensor monitors the amount of rotation happening inside the gearbox itself.

After the transmission’s control module has received the information and determined the rotor velocity, it makes appropriate modifications.

However, repairing your transmission speed sensor is impractical since it just malfunctions. You need to remove it and install a replacement one. Although this symptom indicates a lot of possible scenarios, a skilled technician should assist you in inspecting and diagnosing your car’s speed sensor module.

Speedometer Malfunction

If your car’s speedometer suddenly fails to work, it’s a dead giveaway that your speed sensor has failed. The faulty speed sensor implies that the speedometer cannot indicate your car’s velocity.

 It’s undoubtedly disconcerting not to realize how fast you’re traveling, especially when there are no other vehicles on the highway to assist you in approximating your pace. This might put you in hot water with the police or possibly bring preventable and unwanted car crashes.

Cruise Control Failures

The speed sensors’ primary role is to control the output and input motor rates. However, this is not the sole purpose of these devices. They also examine the cruise controls.

 A car’s cruise control is an automated mechanism that regulates the velocity of your vehicle. Sensors monitoring the transmission’s rates are crucial to its operation.

If it doesn’t operate properly, it’s likely due to faulty sensors. An incorrect signal is sent from the PCM to the ECU, which then powers down. In such a case, it’s best to get in touch with your technician as soon as possible so they can inspect your car.

Check Engine Light On

There are several reasons why your check engine light appears (for example, a bad purge valve); a defective speed sensor is one of them.

The vehicle’s check engine light is crucial as it informs vital engine issues. A defective speed sensor might cause the check engine light to flicker repeatedly and erroneously as you speed up.

 You can retrieve the problem code(s) using a screening tool or automobile OBD scanner, which will assist you in figuring out what your check engine warning signifies. For instance, the diagnostic trouble code P0500 might show up to verify a speed sensor malfunction.

How To Test A Speed Sensor

If you notice the above signs and suspect having a defective speed sensor, follow these steps to test your device:

• See whether there are any transmission speed sensor fault messages on the OBD2 scanner.
• If an error message appears, you know precisely where the issue is and what part has to be replaced. If there are no error messages or if you are using an older vehicle, physical testing of the sensor is necessary.
• Try elevating it from the front to obtain a closer look underneath the car.
• Find your transmission speed sensors on the gearbox casing’s front and rear faces.
• Put a basin or container beneath your speed sensor where oil might escape.
• Following your car’s service booklet instructions, remove the cables from the gearbox casing. Unplug the sensor’s cable connection.
• Switch on the ignition key, yet do not start the motor (all of the keys click over the Accessory). Attach the multimeter or voltmeter tips to the reference wires within the connection.
• A faulty sensor would provide no voltage at all. If, however, the automobile is getting power, you should get it checked out by a professional immediately.

How To Replace A Bad Transmission Speed Sensor

If a speed sensor fails, you need to replace it right away so you can keep tabs on your velocity at all times. It’s also a relatively easy process; thus, if you want to do it yourself and save a few bucks, here is a complete step-by-step guide:

Stop and shut down your car. It’s recommended to give the car 30 minutes to cool down. Elevate the front of your vehicle on jack stands so you can get beneath it.

 Get down low, lay face up beneath the car, and look upward to find the velocity gauge. The device we’re looking for is a little plug protruding vertically from the gearbox’s underside, with an electrical socket attached.

Push the electrical connector’s discharge button. Press harder as you take the plug out of the device.

Take the sensor out with a screwdriver and turn it around until it is slack enough to be removed. Take the sensor out of the gearbox.

Fit the new sensor in position. Turn the sensor around until you can no longer twist it anymore. Attach the electrical connection to the device’s corresponding socket, and it’s all complete! 

FAQs 

Should You Drive With A Defective Speed Sensor?

Although it has been shown that driving is possible without a functional gearbox speed sensor, doing so is strongly discouraged.

A faulty transmission speed sensor may have a domino effect on other parts of the car’s mechanical system; therefore, replacing it as soon as possible is crucial.

 If you notice any warning indications above, fix the problem (if you can) or get in touch with a professional as soon as possible. That way, you won’t have to worry about potential damage to you or your expensive transmissions and motors.

Failing to take preventative measures or replacing a faulty transmission speed sensor might adversely affect the car’s mechanism.

You won’t have to shell out a ton of cash to have them fixed on your own, but doing so is usually highly challenging and will have your vehicle out of operation for quite some time.

How Much Does It Cost To Replace A Transmission Sensor?

The expense of a new speed sensor for a gearbox varies. Depending on the job’s specifics, you might pay between $130 and $170 for service and $50 and $150 for components (not including taxes and other hidden expenses). However, this has nothing to do with the precise position of your car.

Can A Bad Speed Sensor Cause Limp Mode?

Absolutely, a faulty speed sensor will trigger limp mode. A defective speed sensor may cause friction deficit and loss of control. If this continues, the ABS will ultimately cripple the effectiveness of the friction, balance, and control mechanisms, making the vehicle incapable of moving forward.

Wrapping Up 

Hopefully, today’s post has taught you basic transmission speed sensor knowledge, including the transmission speed sensor location, its duties, common signs of a bad sensor, and how to test and replace your malfunctioning speed sensor. 

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